I. Field of the Invention
The present invention relates to a curing system for photohardenable materials of the type used in dental restoration work.
II. Description of the Prior Art
In dentistry, it is oftentimes necessary to restore certain portions of the patient's teeth. For example, such restoration may be required after removal of a cavity from the patient's teeth.
Although gold, amalgam and other metals have been used for such restoration work in the past, in many situations it is more desirable to use a photohardenable material. Such photohardenable materials have a whitish color designed to match the patient's teeth. Thus, once the photohardenable material has been placed on the affected area of the patient's teeth and cured, the restoration becomes invisible or almost invisible, and is thus aesthetically more pleasing than the previously known use of gold and/or amalgam.
There have been two previously known types of light sources used to cure photohardenable materials of the type used in dental restoration work. Specifically, argon lasers have been used to cure such photohardenable materials in a vary rapid time, typically in the range of 5 to 10 seconds. The primary disadvantage of argon lasers, however, is that they are very costly to obtain.
Because of the high cost of argon lasers, incandescent lights, such as halogen lights, have also been used as a light source in order to cure the photohardenable materials in dental applications. Such lights are advantageous over the previously known argon lasers since halogen lights cost in the range of 5-10% of the cost of a comparative argon laser.
A still further disadvantage of the use of halogen lights is that such lights degradate over a period of time. Once the power output from the light decreases, less energy, i.e. power integrated over time, from the light is obtained. Since photohardenable materials require a minimum amount of energy in order to obtain a full cure, the use of an incandescent light for an insufficient time period may result in an inadequate cure of the photohardenable material.